Future DRAM development and prospects for ferroelectric memories

• Published in: Proceedings of 1994 IEEE International Electron Devices Meeting pp. 7 - 16
• Main Author: Tarui, Y.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 1994
• Subjects: Bismuth; Capacitance; Costs; Dielectric materials; Ferroelectric materials; Large scale integration; Nonvolatile memory; Polarization; Random access memory; Very large scale integration
• ISBN: 9780780321113; 0780321111
• ISSN: 0163-1918; 2156-017X
• DOI: 10.1109/IEDM.1994.383474

DRAMs took full advantage of the technical and economical merits of LSI, resulting in cost benefits expressed by "The /spl pi/ rule". In the VLSI era, however, difficulties have arisen with respect to storage capacitance. As a result, cost advantages have been reduced to the level expressed by "The Bi Rule". The use of materials with a high dielectric constant and the use of the polarization reversal current of ferroelectric materials are not perfect solutions to this problem because they are not in accordance with the scaling rule. Ferroelectric memories using the field effect current of a semiconductor by the remanent polarization of the ferroelectric material, however, are in accordance with the scaling rule. The first experimental verification of the nonvolatile memory action was reported by Moll and Tarui in 1963, and this basic memory action has been used in MFS transistors. Ferroelectric memories are nonvolatile and are expected to be high-speed devices, making them suitable for a wide range of applications, but it will be necessary to optimize the interface between the semiconductor and ferroelectric material. This is a worthwhile challenge in the effort to develop new memories for the 21st century.< >